From a16fde8ae7b5c4391a579c925cca5f6b9a523984 Mon Sep 17 00:00:00 2001
From: Daniel <845765@qq.com>
Date: Thu, 14 Dec 2023 22:54:27 +0800
Subject: [PATCH] :art: Add internal kernel API `/api/block/getTailChildBlocks`
 https://github.com/siyuan-note/siyuan/issues/9884

---
 kernel/api/block.go   | 26 +++++++++++++++++++++
 kernel/api/router.go  |  1 +
 kernel/model/block.go | 54 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 81 insertions(+)

diff --git a/kernel/api/block.go b/kernel/api/block.go
index 4ef021bd1..e6d32b2a3 100644
--- a/kernel/api/block.go
+++ b/kernel/api/block.go
@@ -533,3 +533,29 @@ func getChildBlocks(c *gin.Context) {
 
 	ret.Data = model.GetChildBlocks(id)
 }
+
+func getTailChildBlocks(c *gin.Context) {
+	ret := gulu.Ret.NewResult()
+	defer c.JSON(http.StatusOK, ret)
+
+	arg, ok := util.JsonArg(c, ret)
+	if !ok {
+		return
+	}
+
+	id := arg["id"].(string)
+	if util.InvalidIDPattern(id, ret) {
+		return
+	}
+
+	var n int
+	nArg := arg["n"]
+	if nil != nArg {
+		n = int(nArg.(float64))
+	}
+	if 1 > n {
+		n = 7
+	}
+
+	ret.Data = model.GetTailChildBlocks(id, n)
+}
diff --git a/kernel/api/router.go b/kernel/api/router.go
index 4367e4f43..571f78f01 100644
--- a/kernel/api/router.go
+++ b/kernel/api/router.go
@@ -160,6 +160,7 @@ func ServeAPI(ginServer *gin.Engine) {
 	ginServer.Handle("POST", "/api/block/getBlockDOM", model.CheckAuth, getBlockDOM)
 	ginServer.Handle("POST", "/api/block/getBlockKramdown", model.CheckAuth, getBlockKramdown)
 	ginServer.Handle("POST", "/api/block/getChildBlocks", model.CheckAuth, getChildBlocks)
+	ginServer.Handle("POST", "/api/block/getTailChildBlocks", model.CheckAuth, getTailChildBlocks)
 	ginServer.Handle("POST", "/api/block/getBlockBreadcrumb", model.CheckAuth, getBlockBreadcrumb)
 	ginServer.Handle("POST", "/api/block/getBlockIndex", model.CheckAuth, getBlockIndex)
 	ginServer.Handle("POST", "/api/block/getRefIDs", model.CheckAuth, getRefIDs)
diff --git a/kernel/model/block.go b/kernel/model/block.go
index 3309d1e74..9d9a88063 100644
--- a/kernel/model/block.go
+++ b/kernel/model/block.go
@@ -546,6 +546,60 @@ func GetChildBlocks(id string) (ret []*ChildBlock) {
 	return
 }
 
+func GetTailChildBlocks(id string, n int) (ret []*ChildBlock) {
+	ret = []*ChildBlock{}
+	if "" == id {
+		return
+	}
+
+	tree, err := loadTreeByBlockID(id)
+	if nil != err {
+		return
+	}
+
+	node := treenode.GetNodeInTree(tree, id)
+	if nil == node {
+		return
+	}
+
+	if ast.NodeHeading == node.Type {
+		children := treenode.HeadingChildren(node)
+		for i := len(children) - 1; 0 <= i; i-- {
+			c := children[i]
+			ret = append(ret, &ChildBlock{
+				ID:      c.ID,
+				Type:    treenode.TypeAbbr(c.Type.String()),
+				SubType: treenode.SubTypeAbbr(c),
+			})
+			if n == len(ret) {
+				return
+			}
+		}
+		return
+	}
+
+	if !node.IsContainerBlock() {
+		return
+	}
+
+	for c := node.LastChild; nil != c; c = c.Previous {
+		if !c.IsBlock() {
+			continue
+		}
+
+		ret = append(ret, &ChildBlock{
+			ID:      c.ID,
+			Type:    treenode.TypeAbbr(c.Type.String()),
+			SubType: treenode.SubTypeAbbr(c),
+		})
+
+		if n == len(ret) {
+			return
+		}
+	}
+	return
+}
+
 func GetBlock(id string, tree *parse.Tree) (ret *Block, err error) {
 	ret, err = getBlock(id, tree)
 	return